The present invention is related to a rotary wrench in which the working head can be conveniently tightened or loosened to adjust the angle of the working head for different operations.
FIG. 1 shows a conventional rotary wrench including a handle 10, a working head 14 and a locking member 16.
A front end of the handle 10 is formed with a holding space 11 defined between two arms. The arms are formed with opposite pivot holes 12. An elongated split 13 longitudinally extends from the bottom of the holding space 11 toward a rear end of the handle 10. In addition, the two arms are respectively formed with a through hole and a thread hole opposite to each other. Two pivot shafts 15 are disposed on two sides of the working head 14. The pivot shafts 15 are fitted in the pivot holes 12 of the arms to pivotally connect the working head 14 with the handle 10. In addition, the working head 14 has a coupling section 16 for coupling with a socket. The locking member 17 is passed through the through hole and screwed into the thread hole of the arms of the handle 10. When the working head 14 is rotated relative to the handle 10 to a desired angular position, the locking member 17 can be tightened to contract the two arms and narrow the holding space 11. At this time, the working head 14 is tightly clamped by the arms and fixed in the angular position. However, in actual operation, such conventional rotary wrench has some shortcomings as follows:                1. When the working head 14 is rotated relative to the handle 10, the coupling section 16 of the working head 14 will abut against the bottom wall of the holding space 11. Therefore, the rotational angle of the working head 14 is restricted within a certain range. This makes it inconvenient to operate the conventional rotary wrench.        2. The two arms of the handle 10 are respectively formed with the through hole and the thread hole opposite to the through hole. The locking member 17 is passed through the through hole and screwed into the thread hole of the arms to force the arms to tightly clamp the working head 14 and fix the working head 14 in a desired angular position. In manufacturing, it is necessary to drill holes on the arms and tap one of the holes for locking the locking member 17. This procedure leads to increment of the manufacturing cost.        